UPDATE 9:34 AM
The northbound Interstate 5 is open again after having been closed at Parker Road due to weather conditions, said Officer John Lutz of the California Highway Patrol. The hard closure began around 8:00 AM, but the CHP was able to open the highway again after plowing away the snow.
Stuart Seto of the National Weather Service said that difficult driving conditions may continue through the Grapevine until around noontime today, when the snow and slush begin to melt off.